All scorpions are poisonous, most in north america are not considered deadly however. They range in general severity between that of a bee sting and the bite of a rattlesnake. If you are sensitive to stings and bites of insects you should be very wary though. Some people that are allergic will be dead within minutes of any type of sting that may be set off the allergy bee, wasp or scorpion. If you get stung you can expect some pain and/or sickness but are unlikely to be killed. It also may not be a native species (I personally have never heard of scorpions in Tennessee) but an escaped pet, or non-native invader.
